On the Possibility of Metal Borides for Hydrodesulfurization

We have explored cobalt and nickel boride-based catalysts for the hydrodesulfurization (HDS) of thiophene and evaluate their overall catalytic activity, mode of desulfurization, and stability to sulfo-reductive reaction conditions. While the prepared cobalt and nickel borides promote hydrodesulfurization, flow-reactor studies measuring the catalytic activity show that, in actuality, these materials are unstable with respect to the metal sulfides under HDS conditions. In fact, the observed catalytic HDS results from the conversion of the metal boride, and any impurity oxides, to the corresponding metal sulfide. These results include confirmation from characterization of the used catalysts by EDX, powder XRD, and elemental analysis.